Brian Souter, chief executive of Stagecoach, has saved himself up to £5m by transferring 22 million shares in his company to a family trust before new capital gains tax rules come into force at the weekend.

Mr Souter yesterday transferred shares worth £54m into a trust set up for the benefit of his wife, Betty, just four days before the capital gains tax rate on such transactions rises from 10 per cent to 18 per cent.

Ann Gloag, Mr Souter's sister and co-founder of Stagecoach, who is now a non-executive director at the transport group, also took action to beat the tax increase, transferring around 11.5 million shares into other family trusts.

The Stagecoach directors are just the latest in a series of well-known business people who have reorganised their shareholdings to beat the controversial reforms to capital gains tax announced last October by Alistair Darling.

Despite a furious reaction from business groups, Mr Darling refused in last month's Budget to back down on his CGT proposals, under which a series of reliefs for long-term ownership of business assets will be replaced with a flat-rate tax charged at 18 per cent. Currently, those who own their own businesses, or shares in their companies, pay as little as 10 per cent when selling the assets.

Rightmove, the online estate agency, also said yesterday that one of its non-executive directors, Jonathan Agnew, had disposed of a large shareholding "for tax-planning purposes".

On Tuesday, the London Stock Exchange said Clara Furse, its chief executive, had transferred £5.1m worth of shares in the bourse to her husband, reducing her potential tax bill on the holding by more than £400,000.

Other well-known figures have made much more substantial disposals or transfers. Lord Sainsbury, a significant donor to the Labour Party, reduced his potential tax bill on shares in the supermarket group by £27m after moving ownership of his £340m stake to another company under his control. Ken Clarke, the former Conservative chancellor who is deputy chairman of British American Tobacco, Chris Wright, founder of the Chrysalis music group, and Rob Templeman, chief executive of Debenhams, have all reorganised share holdings.

The CGT reforms have also led to an unusually high number of small business owners putting their companies up for sale, in a bid to cash in before the new higher rate becomes payable. They include James Dyson, who has sold a large stake in his vacuum cleaner business, and Will Chase, founder of Tyrells, the crisps manufacturer.

Mike Warburton, a senior tax partner at Grant Thornton, said: "Ever since October, we have been on alert [to the fact] that people would want to sell their businesses, or their shares in listed companies – people are triggering their gains over so that they can pay tax at 10 per cent rather than 18 per cent."